Field of the Invention
The invention relates to an elastic mount, especially, an engine mount for motor vehicles. The mount includes at least two resilient elements connected in parallel to each other, a force applicator connecting a source of vibration to the at least two resilient elements, and a selectable couple for connecting the force applicator thereto.
An elastic mount is disclosed in German Published, Non-Prosecuted Patent Application DE 41 28 761.4 A, corresponding to U.S. Pat. No. 5,213,315 to Hartel et al. In the Hartel configuration, two resilient elements are connected in parallel. Each of the elements has an elastomeric resilient body. One of the resilient bodies is configured as a tubular cylinder and accommodates the second resilient body in its interior. The interior resilient element is a force applicator that is selectable by a couple to enable a variance of the stiffness of the elastic mount as a function of the vehicle ride. The couple includes a coupling element defined on the resilient element. The coupling element is force-lockingly connectable to a second coupling element. A force-locking connection is one that connects two elements together by force external to the elements, as opposed to a form-locking connection, which is provided by the shapes of the elements themselves. A hydraulically activated diaphragm achieves the change in movement. In the prior art engine mount, the travel and force components needed to select the coupling elements are relatively high. Furthermore, in the released condition, no axial decoupling of the second resilient element is provided.
German Published, Non-Prosecuted Patent Application DE 41 39 046 A discloses another engine mount in which the resilient element is configured as an elastomeric tubular cylinder disposed between a mounting plate at the engine end and a mounting plate at the vehicle body end. Provided below the mounting plate at the vehicle body end is a hydraulic damping mount configured as a two-chamber mount. While the tubular cylindrical resilient block produces high damping of material-borne noise, the parallel-connected hydraulic mount serves to damp low-frequency vibration. The application does not provide for or disclose a stiffness selection for the engine mount.